The purpose of this research project is to investigate the general and tumor-directed cellular immune responses of patients with bladder carcinoma. These studies are necessary in order to delineate and to understand the role of cellular immune responses in the control of the incidence and spread of cancer of the urinary bladder. Studies are directed at measuring the general immune responsiveness in terms of Mixed Leukocyte Culture reactivity and mitogen stimulation in relation to tumor burden. In addition, an analysis is being made of the role of suppressor cells in the immunological hyporesponsiveness in vitro of some of these patients. Studies on specific immune responsiveness of these patients are directed to answering the question as to whether bladder cancer patients have cytotoxic blood T cells directed against tumor cell antigens in vitro.